New problem, new topic. For the sake of order and to help anyone experiencing similar issues later on.

I have bought a license but can not activate my software. Entering the serial as intended in the start-up box and clicking 'activate' gives no result. Clicking a few more times (approx. 10 times) gives a pop-up with an error message, "An exception of class NilObjectException was not handled. The application must shut down.", see attached file.

I then tried to use the remote activator, however that gives the exact same error message and shuts down as well.

Sorry about that. Seems you're encountering a known bug on Macs. Please see this blog post for a workaround. Please note the workaround must be done in the global /Library folder, not your user ~/Library folder.